DOE Brightens Trend on Solid State Lighting
A new forecast presented by the US Department of Energy (DOE) shows that solid state lighting development is progressing even faster than predicted. Review of the 2008 DOE Solid-State Lighting R&D Workshop entitled “Transformations in Lighting” held January 29-31, 2008 in Atlanta, GA reveals an important new trend in solid state lighting development. Fred Welsh speaking at the workshop stated, “LED efficacies far-surpassed our projections.”
We have plotted data from the workshop and show comparisons of DOE forecasts for progress in light emitting diode (LED) solid state lighting (SSL) in Figures 1 and 2 below.

Figure 1: Forecast Trend for Luminous Efficacy of LED SSL Laboratory Results (Source: US DOE)

Figure 2: Forecast Trend for Luminous Efficacy of LED SSL Results for Commercial Warm White Lamps (Source: US DOE)
Figure 1 and 2 compare DOE’s forecasts for LED SSL performance (luminous efficacy) for both Laboratory (Figure 1) and Commercial Warm White (Figure 2) lamps as of March 2007 and as reported at the Atlanta Workshop in January 2008. Both Figures also show the efficacy range of fluorescent tubes and compact fluorescent lamps. This comparison of SSL performance forecasts made only 11 months apart is striking. Moreover, the more recent forecast reflects a more realistic view of how technologies advance.
The straight line (linear without upper bound) increase in efficacy shown in the March ’07 forecast of Figures 1 and 2 is clearly not realistic but reflects the near linear advance of performance during the early development of a technology. The forecast from January ’08 illustrates that more rapid than previously forecast progress has in fact occurred and is forecast to continue through 2015. The updated forecast more realistically reflects that technology improvements can be rapid in “early days” but will trend asymptotically toward physical limits as the technology matures.
All in all, this is a good news story for the solid state lighting industry. LEDs are improving even more rapidly than some had forecast. No doubt, this rapid progress is due to the R&D support and focus provided by the DOE program, and even more by efforts that businesses have committed to make energy efficient solid state lighting a reality. As strong progress is made on LED lamp improvements, focus is also moving on to include the vitally important issue of the performance of these lamps in actual luminaire applications. Clearly, we are approaching a time when energy saving lighting will be come a reality. As consumers and governments adopt the notion that solid state lighting will lead to both energy conservation and cost reductions, businesses in the SSL industry will see attractive valuations and opportunities.
Date: February 25, 2008
Categories: Green Technology, Investment, Optoelectronics, Solid State Lighting